Unit 1 - AOS2 - Changes in environment Flashcards
Daily changes - define and example
- Short term and follows the cercadian cycle
- Nocturnal (active at night)
- Diurnal (active during the day)
- Crepuscular (active at dawn and dust)
Cercadian cycle
Physical, mental and behavioural changes that follow the 24 hour cycle.
- respond primarily to light and dark
Monthly changes - define and examples
- Short term
- relates to lunar-tidal rhythms
Lunar-tidal rhythms
The positioning of the moon effects the tide.
- where the moon is high tide across the whole of earth on both sides.
- Effects animals that hunt for food and high or low tides etc.
Seasonal changes - cause and effect
cause - the tilt of the earth’s axis and distance from the sun.
Effect - changes the light availability, temperature, rainfall, Level of activity from animals.
Describe the most common event that caused the extinction for dinosaurs in each of the earths systems and why
Biosphere - extinction of animals (due to rapid change, lower food available)
Hydrosphere - tsunami, acid rain, dust clouds (prevents photosynthesis)
Atmosphere - Limited oxygen supply
Lithosphere - Chunks of earth rock re-fell from comets etc. and caused fires.
Megafauna, examples and what caused them to go extinct.
Extremely large animals (wombats, lizards (Comodo dragon)
Cause for extinction: increased temp, reduced water availability.
Define mass extinction
is a short period of time in which a high percentage of biodiversity or distinct species dies out.
Eccentricity (Milankovitch Cycle)
Changes the shape of the earths orbit around the sun, changing the distance from the sun.
- Responsible for the different length of seasons on earth. (e.g. shorter winters, longer summers …)
Obliquity (Milankovitch Cycle)
It is the change in the angle of the earth tilt
- Effects the distance of countries and different points of earth from the sun
- The greater Earth’s axial tilt angle, the more extreme our seasons are, as each hemisphere receives more solar radiation during its summer, when the hemisphere is tilted toward the Sun, and less during winter, when it is tilted away.
Precession (Milankovitch Cycle)
As the earth rotates, it wobbles slightly upon its axis, like a slightly off-center spinning top.
- It affects seasons by making the seasonal contrast more extreme in one hemisphere and less extreme in the other.
Ecological succession
Gradual change in structure and species composition of an ecosystem over time
Primary succession
- when a community becomes established on a previously un-vegetated surface
- first species to grow are called colonisers or pioneer species.
Secondary succession
occurs in an area that previously supported a biological community that has undergone some change or distribution.
Drought
is a prolonged dry period in the natural climate cycle that can occur anywhere in the world.
- Satellite imagery can find drought effected areas
